Solar cell grading A, B, C, D
With solar cells accounting for 60%+ of the solar panel manufacturing costs, solar cells are the number one component used to cut overall costs of a solar panel.
1. Grade A solar cells
Grade A cells are simply without any visible defects, and the electrical data are in spec.
The specifications of the cells can be measured with cell testing equipment.
The perfect grade A cell may still have a slight bend of 2.0mm and a tiny color deviation is permitted.
Below a grade A solar cell. Due to the light the color seems to deviate, but in fact, this is a flawless solar cell:
2. Grade B solar cells
Grade B cells have visible but tiny defects, and the electrical data are in spec.
The following visible defects are common:
1. Slight bend of 2.0mm to 2.5mm
2. Color deviation, Visible yellow area takes more than 1/4 area of total on the Surface
3. Missing prints greater than 0.5mm
5. Paste leakage
7. Water marks
Here a couple of examples of Grade B solar cells:
3. Grade C solar cells
A Grade C solar cell has visible defects, and the electrical data are off-spec.
All solar cells with defects worse than Grade B can be classified as Grade C.
A solar cell can be graded as C when the partly broken cell which could be cut into smaller pieces and re-used.
Here are a number of Grade C solar cell examples:
4. Grade D solar cells
A Grade D solar cell is broken and can not be cut in smaller cells. There’s not much you can do with these.